@book {bibliotheque_nationale_lettre_1990,
	title = {La Lettre - Biblioth{\`e}que nationale},
	year = {1990},
	publisher = {Biblioth{\`e}que nationale},
	organization = {Biblioth{\`e}que nationale},
	address = {Paris},
	author = {Biblioth{\`e}que nationale (France)}
}
